The present invention relates generally to fluid pumping devices, and more particularly provides a uniquely constructed and operative piezoelectric air pump used to deliver supply air to fluidic devices or systems.
Various types of air pumping mechanisms have heretofore been utilized to supply pressurized air to "fluidic" devices--devices which use small, high velocity air jets to perform various control and sensing functions, as opposed to more conventional mechanical or electrical control and sensing devices. However, for a variety of reasons, none of these prior pumping mechanisms has proven to be entirely satisfactory in fluidic air supply applications.
As an example, solenoid-operated reciprocating diaphragm pumps have been utilized. This type of pump, though fairly simple in construction, has the disadvantages, in fluidic applications, of undesirable low frequency operation pressure ripple, and acceleration sensitivity due to the relatively high diaphragm mass required.
Piezoelectrically driven diaphragm pumps have, for some time, been considered as possible alternatives to electromagnetically driven pumps due to the well-known piezoelectric drive characteristics of lighter weight, greater frequency response and considerably smaller size. However, in practice, the utilization of piezoelectric drives in fluidic air supply pumps has heretofore not resulted in wholly satisfactory structural simplicity, compactness, supply flow characteristics or pumping efficiency.
Accordingly, it is an object of the present invention to provide a piezoelectric fluidic air supply pump having, compared to conventional piezoelectric air pumps, improved structural and functional characteristics.